having depopulated the "Wakuafi wilderness" in what is now southeastern Kenya, Maasai warriors threatened Mombasa on the Kenyan coast.

Because of this migration the Maasai are the southernmost Nilotic speakers. The period of expansion was followed by the Maasai "Emutai" of 1883-1902. This period was marked by epidemics of contagious bovine pleuropneumonia, rinderpest (see 1890s African rinderpest epizootic)